Router>: User mode = Limited to basic monitoring commands Router#: Privileged mode (exec-level mode) = Provides access to all other router commands Router(config)#: global configuration mode = Commands that affect the entire system Router(config-if)#: interface mode = Commands that affect interfaces Router(config-subif)#: subinterface mode = Commands that affect subinterfaces Router(config-line)#: line mode = Commands that affect in lines modes (console, vty, aux) Router(config-router)#: router configuration modeChanging switch hostname:1Switch(config)# hostname SW1

Configuring passwords:12SW1(config)# enable secret cisco ! MD5 hashSW1(config)# enable password notcisco ! Clear text

Securing console port:123SW1(config)# line con 0SW1(config-line)# password ciscoSW1(config-line)# login

Securing terminal lines:123SW1(config)# line vty 0 4SW1(config-line)# password ciscoSW1(config-line)# login

Encrypting passwords:1SW1(config)# service password-encryption

Configuring banners:12345SW1(config)# banner motd $-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-UNAUTHORIZED ACCESS IS PROHIBITED-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-$

Giving the switch an IP address:123SW1(config)# interface vlan 1SW1(config-if)# ip address 172.16.1.11 255.255.255.0 ! or DHCPSW1(config-if)# no shutdown

Setting the default gateway:1SW1(config)# ip default-gateway 172.16.1.1

Saving configuration:123456789SW1# copy running-config startup-configDestination filename [startup-config]? ! Press enter to confirm file name.Building configuration[OK]! Short for write memory.SW1# wrBuilding configuration[OK]

Working environment:name lookup, history, exec-timeout and logging behavior, also valid for line con 0.12345SW1(config)# no ip domain-lookupSW1(config)# line vty 0 4SW1(config-line)# history size 15SW1(config-line)# exec-timeout 10 30SW1(config-line)# logging synchronous

Configuring switch to use SSH: Configure DNS domain name:1SW1(config)# ip domain-name example.com

Configure a username and password:1SW1(config)# username admin password cisco

Generate encryption keys:The size of the key modulus in the range of 360 to 204812SW1(config)# crypto key generate rsaHow many bits in the modulus [512]: 1024

Define SSH version to use:1SW1(config)# ip ssh version 2

Enable vty lines to use SSH:1234SW1(config)# line vty 0 4SW1(config-line)# login local! You can set vty lines to use only telnet or only ssh or both as in the example.SW1(config-line)# transport input telnet ssh

Aliases:Used to create shortcuts for long commands.123SW1(config)# alias exec c configure terminalSW1(config)# alias exec s show ip interface briefSW1(config)# alias exec sr show running-config

Description, speed and duplex:123456SW1(config)# interface fastEthernet 0/1SW1(config-if)# description LINK TO INTERNET ROUTERSW1(config-if)# speed 100 ! Options: 10, 100, auto! The range keyword used to set a group of interfaces at once.SW1(config)# interface range fastEthernet 0/5 10SW1(config-if-range)# duplex full (options: half, full, auto)

Verify Basic Configuration: Shows information about the switch and its interfaces, RAM, NVRAM, flash, IOS, etc.1SW1# show version

Shows the current configuration file stored in DRAM.1SW1# show running-config

Shows the configuration file stored in NVRAM which is used at first boot process.1SW1# show startup-config

Lists the commands currently held in the history buffer.1SW1# show history

Shows an overview of all interfaces, their physical status, protocol status and ip address if assigned.1SW1# show ip interface brief

Shows detailed information about the specified interface, its status, protocol, duplex, speed, encapsulation, last 5 min traffic.1SW1# show interface vlan 1

Shows the description of all interfaces1SW1# show interfaces description

Shows the status of all interfaces like connected or not, speed, duplex, trunk or access vlan.1SW1# show interfaces status

Shows the public encryption key used for SSH.1SW1# show crypto key mypubkey rsa

Shows information about the leased IP address (when an interface is configured to get IP address via a dhcp server)1SW1# show dhcp lease

Configuring port security: Make the switch interface as access port:1SW1(config-if)# switchport mode access

Enable port security on the interface:1SW1(config-if)# switchport port-security

Specify the maximum number of allowed MAC addresses:1SW1(config-if)# switchport port-security maximum 1

Define the action to take when violation occurs:1SW1(config-if)# switchport port-security violation shutdown ! options: shutdown, protect, restrict

Specify the allowed MAC addresses:The sticky keyword is used to let the interface dynamically learns and configures the MAC addresses of the currently connected hosts.1SW1(config-if)# switchport port-security mac-address 68b5.9965.1195 ! options: H.H.H, sticky

Verify and troubleshoot port security: Shows the entries of the mac address table:1SW1# show mac-address-table

Overview of port security of all interfaces:1SW1# show port-security

Shows detailed information about port security on the specified interface:1SW1# show port-security interface fa0/5

Configuring VLANs: Create a new VLAN and give it a name:12SW1(config)# vlan 10SW1(config-vlan)# name SALES

Assign an access interface to access a specific VLAN:123SW1(config)# interface fastEthernet 0/5SW1(config-if)# switchport mode accessSW1(config-if)# switchport access vlan 10

Configuring an auxiliary VLAN for cisco IP phones:1234SW1(config)# interface fastEthernet 0/5! accessing vlan 10 (data) and 12 (VoIP)SW1(config-if) #switchport access vlan 10SW1(config-if) #switchport voice vlan 12

Configuring Trunks:123SW1(config)# interface fastEthernet 0/1SW1(config-if)# switchport mode trunk ! options: access, trunk, dynamic auto, dynamic desirableSW1(config-if)# switchport trunk allowed vlan add 10 ! options: add, remove, all, except

Securing VLANs and Trunking: Administratively disable unused interfaces:1SW1(config-if)# shutdown

Prevent trunking by disabling auto negotiation on the interface:12SW1(config-if)# nonegotiate ! or hardcode the port asan access portSW1(config-if)# switchport mode access

Assign the port to an unused VLAN:1SW1(config-if)# switchport access vlan 222

Configuring VTP: Configure VTP mode:The transparent VTP mode is used when an engineer wants to deactivate VTP on a particular switch1SW1(config)# vtp mode server ! options: server, client, transparent

Configure VTP domain name:1SW1(config)# vtp domain EXAMPLE ! case-sensitive

Configure VTP password (optional):1SW1(config)# vtp password cisco ! case-sensitive

Configure VTP pruning (optional):1SW1(config)# vtp pruning ! only works on VTP servers

Enable VTP version 2 (optional):1SW1(config)# vtp version 2

Verify and troubleshoot VLANs and VTP: Lists information about administrative setting and operation status of interface:1SW1# show interfaces if switchport

Lists all the trunk ports on a switch including the trunk allowed VLANs:1SW1# show interfaces trunk

Lists information about the VLANs:1SW1# show vlan {brief | id | name | summary}

Lists VTP configuration (mode, domain-name, version, etc) and revision number:1SW1# show vtp status

Shows the VTP password:1SW1# show vtp password

STP optimization: Hard coding the root bridge (changing bridge priority):1234SW1(config)# spanning-tree vlan 1 root primarySW1(config)# spanning-tree vlan 1 root secondary! Priority must be a multiply of 4096SW1(config)# spanning-tree [vlan 1]priority 8192

Changing the STP mode:1SW1(config)# spanning-tree mode rapid-pvst ! options: mst, pvst, rapid-pvst

Enabling portfast and BPDU guard on an interface:Portfast and BPDU guard are enabled only on interfaces connected to end user hosts12SW1(config-if)# spanning-tree portfastSW1(config-if)# spanning-tree bpduguard enable

Changing port cost:1SW1(config-if)# spanning-tree [vlan 1] cost 25

Bundling interfaces into an etherchannel:1SW1(config-if)# channel-group 1 mode on ! options: auto, desirable, on

STP verification and troubleshooting: Shows detailed info about STP state:1SW1# show spanning-tree

Shows STP info only on a specific port:1SW1# show spanning-tree interface fa0/2

Shows STP info only for a specific VLAN:1SW1# show spanning-tree vlan 1

Shows info about the root switch:1SW1# show spanning-tree [vlan 1] root

Shows info about the local switch:1SW1# show spanning-tree [vlan 1] bridge

Show the state of the etherchannels:1SW1# show etherchannel 1

Provides informational messages about the changes in the STP topology:1SW1# debug spanning-tree events

Enabling or disabling CDP: Enabling CDP globally on a switch:1SW1(config)# cdp run

Disabling CDP on a given interface:1SW1(config-if)# no cdp enable

Using CDP for network verification and troubleshooting: Shows global information about CDP itself:1SW1# show cdp

Shows information about CDP on a specific interface:1SW1# show cdp interface fa0/2

Shows information about the directly connected cisco devices including interfaces names capabilities:1SW1# show cdp neighbors

Shows detailed information about the neighboring cisco devices including device address and version of IOS they run:123SW1# show cdp neighbors detail! ORSW1# show cdp entry *

Shows detailed information about the specified entry only:1SW1# show cdp entry SW2

Router basic configuration:This section includes IOS commands that are absolutely identical on both routers and switches, except the part ofline aux 0which is configured only on router because switches do not have an auxiliary port.1234567891011121314151617181920212223242526272829303132333435363738Router(config)# hostname R1R1(config)# enable secret ciscoR1(config)# line con 0R1(config-line)# password ciscoR1(config-line)# loginR1(config-line)# logging synchronousR1(config-line)# exec-timeout 30 0R1(config-line)# exitR1(config)# line vty 0 4R1(config-line)# password ciscoR1(config-line)# loginR1(config-line)# logging synchronousR1(config-line)# exec-timeout 30 0R1(config-line)# exitR1(config)# line aux 0R1(config-line)# password ciscoR1(config-line)# loginR1(config-line)# logging synchronousR1(config-line)# exec-timeout 30 0R1(config-line)# exitR1(config)# banner motd $-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-UNAUTHORIZED ACCESS IS PROHIBITED-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-$R1(config)# alias exec c configure terminalR1(config)# alias exec s show ip interface briefR1(config)# alias exec sr show running-configR1(config)# no ip domain-lookupR1(config)# service password-encryptionR1(config)# ip domain-name example.comR1(config)# username admin password ciscoR1(config)# crypto key generate rsaHow many bits in the modulus [512]: 1024R1(config)# ip ssh version 2R1(config)# line vty 0 4R1(config-line)# login localR1(config-line)# transport input telnet ssh

Configuring router interfaces:Clock rate is set only on the DCE side, typically the ISP side. On your router which is DTE you dont need to set clocking.12345678910R1(config)# interface fastEthernet 0/0R1(config-if)# description LINK TO LOCAL LAN THROUGH SW1R1(config-if)# ip address 172.16.1.1 255.255.255.0R1(config-if)# no shutdownR1(config-if)# exitR1(config)# interface serial 0/1/0R1(config-if)# description WAN CONNECTION TO R2R1(config-if)# ip address 10.1.1.1 255.255.255.252R1(config-if)# clock rate 128000R1(config-if)# no shutdown

Configuring Router-On-Stick for vlan routing:12345678R1(config)# interface fastEthernet 0/0R1(config-if)# no shutdownR1(config)# interface fastEthernet 0/0.10R1(config-subif)# encapsulation dot1q 10R1(config-subif)# ip address 192.168.10.1 255.255.255.0R1(config-subif)# interface fastEthernet 0/0.20R1(config-subif)# encapsulation dot1q 20R1(config-subif)# ip address 192.168.20.1 255.255.255.0

Static route: Using next hop:1R1(config)# ip route 10.1.2.0 255.255.255.0 10.1.128.1

Using exit interface:12R1(config)# ip route 10.1.2.0 255.255.255.0 Serial 0/0*Note: Exit interface can be used in point-to-point serial links.

Default Route:1R1(config)# ip route 0.0.0.0 0.0.0.0 199.1.1.1

RIPv2 Configuration:12345R1(config)# router ripR1(config-router)# version 2R1(config-router)# network 10.0.0.0 ! written as an original class AR1(config-router)# no auto-summaryR1(config-router)# passive-interface serial 0/0

RIPv2 Verification: Shows information about the running routing protocol process:1R1# show ip protocols

Shows the entire routing table:1R1# show ip route

Shows routes learned via RIP only:1R1# show ip route rip

Shows detailed information about the route to the specified destination network:1R1# show ip route 10.1.1.1

OSPF Configuration: Enter OSPF router configuration mode:1R1(config)# router ospf 10 ! 10 = process ID

Configure one or more network commands to identify which interfaces will run OSPF:123R1(config-router)# network 10.0.0.0 0.255.255.255 area 0R1(config-router)# network 172.16.8.0 0.0.7.255 area 0R1(config-router)# network 192.168.1.254 0.0.0.0 area 1

Configure router ID either (Optional):Using router-id ospf subcommand:1R1(config-router)# router-id 1.1.1.1

Configuring an IP address on a loopback interface:12R1(config)# interface loopback 0R1(config-if)# ip address 1.1.1.1 255.255.255.255

Change Hello and Dead intervals per interface (Optional):12R1(config-if)# ip ospf hello-interval 2R1(config-if)# ip ospf dead-interval 6

Impact routing choices by tuning interface cost using one of the following ways (Optional):Changing interface cost:1R1(config-if)# ip ospf cost 55

Changing interface bandwidth:1R1(config-if)# bandwidth 128 ! in Kbps

Changing the reference bandwidth that used by OSPF to calculate the cost:1R1(config-router)# auto-cost reference-bandwidth 1000 ! in Mbps

Disabling OSPF on a certain interface (Optional):1R1(config-router)# passive-interface serial 0/0

Configuring OSPF authentication (Optional):Type 0 authentication (none):1R1(config-if)# ip ospf authentication null

Type 1 authentication (clear text):12R1(config-if)# ip ospf authenticationR1(config-if)# ip ospf authentication-key cisco

Type 2 authentication (md5):12R1(config-if)# ip ospf authentication message-digestR1(config-if)# ip ospf message-digest-key 1 md5 cisco

Configure maximum equal-cost paths (Optional):1R1(config-router)# maximum paths 6

OSPF verification: Shows information about the running routing protocol process:1R1# show ip protocols

Shows the entire routing table:1R1# show ip route

Shows routes learned via OSPF only:1R1# show ip route ospf

Shows all neighboring routers along with their respective adjacency state:1R1# show ip ospf neighbors

Shows all the information contained in the LSDB:1R1# show ip ospf database

Shows detailed information about OSPF running on a specific interface:1R1# show ip ospf interfaces serial 0/0

EIGRP Configuration: Enter EIGRP configuration mode and define AS number:1R1(config)# router eigrp 121 ! 121 = AS number

Configure one or more network commands to enable EIGRP on the specified interfaces:1234R1(config-router)# network 10.0.0.0R1(config-router)# network 172.16.0.0 0.0.3.255R1(config-router)# network 192.168.1.1 0.0.0.0R1(config-router)# network 0.0.0.0 255.255.255.255

Disable auto summarization (Optional):1R1(config-router)# no auto-summary

Disable EIGRP on a specific interface (Optional):1R1(config-router)# passive-interface serial 0/0

Configure load balancing parameters (Optional):12R1(config-router)# maximum-paths 6R1(config-router)# variance 4

Change interface Hello and Hold timers (Optional):12R1(config-if)# ip hello-interval eigrp 121 3R1(config-if)# ip hold-time eigrp 121 10

Impacting metric calculations by tuning BW and delay of the interface (Optional):12R1(config-if)# bandwidth 265 ! in Kbps)R1(config-if)# delay 120 ! tens of microseconds

EIGRP Authentication:Thekey-stringvalue and the mode must be the same on both routers. Lifetime options of the keys requires the clock of the routers to be set correctly, better use NTP, or it can cause problems Create an authentication key chain as follows:Create a key chain and give it a name:1R1(config)# key chain MY_KEYS

Create one or more keys giving them numbers:1R1(config-keychain)# key 1

Define the key value:1R1(config-keychain-key)# key-string1stKEY

Define the life time of the keys (optional):12R1(config-keychain-key)# send-lifetime [start time] [end time]R1(config-keychain-key)# accept-lifetime [start time] [end time]

Enable md5 authentication mode for EIGRP on the interface:1R1(config-if)# ip authentication mode eigrp121 md5

Refer to the correct key chain to be used on the interface:1R1(config-if)# ip authentication key-chain eigrp121 MY_KEYS

EIGRP Verification: Shows routes learned via EIGRP only:1R1# show ip route eigrp

Shows EIGRP neighbors and status:1R1# show ip eigrp neighbors

Shows EIGRP topology table, including successor and feasible successor:1R1# show ip eigrp topology

Shows interfaces that run EIGRP:1R1# show ip eigrp interfaces

Lists statistics on numbers of EIGRP messages sent and received by the router:1R1# show ip eigrp traffic

Access Control Lists:Standard ACL: 1 99 and 1300 1999 Use a remark to describe the ACL (Optional):1R1(config)# access-list 1 remark ACL TO DENY ACCESS FROM SALES VLAN

Create the ACL, keeping the following in mind: ACL uses first-match logic. There is an implicit deny anyat the end of the ACL.12345R1(config)# access-list 2 deny 192.168.1.77R1(config)# access-list 2 deny 192.168.1.64 0.0.0.31R1(config)# access-list 2 permit 10.1.0.0 0.0.255.255R1(config)# access-list 2 deny 10.0.0.0 0.255.255.255R1(config)# access-list 2 permit any

Enable the ACL on the chosen router interface in the correct direction (in or out):1R1(config-if)# ip access-group 2 out

Using standard ACL to limit telnet and SSH access to a router:Create the ACL that defines the permitted telnet clients:12R1(config)# access-list 99 remark ALLOWED TELNET CLIENTSR1(config)# access-list 99 permit 192.168.1.128 0.0.0.15

Apply the ACL inbound the vty lines12R1(config)# line vty 0 4R1(config-line)# access-class 99 in

Extended ACL: 100 199 and 2000 2699 Extended ACL should be placed as close as possible to the source of the packet. Extended ACL matches packets based on source & des.IP addresses, protocol, source & des. Port numbers andother criteria as well123456789R1(config)# access-list 101 remark MY_ACCESS_LISTR1(config)# access-list 101 deny iphost 10.1.1.1 host 10.2.2.2R1(config)# access-list 101 deny tcp 10.1.1.0 0.0.0.255 any eq 23R1(config)# access-list 101 deny icmp 10.1.1.1 0.0.0.0 anyR1(config)# access-list 101 deny tcphost 10.1.1.0 host 10.0.0.1 eq 80R1(config)# access-list 101 deny udphost 10.1.1.7 eq 53 anyR1(config)# access-list 101 permit ip any anyR1(config)# interface fastEthernet 0/0R1(config-if)# ip access-group 101 in

Named ACL: Named ACLs use names to identify ACLs rather than numbers, and commands that permit or deny traffic are written in a sub mode called named ACL mode (nacl). Named ACL enables the editing of the ACL (deleting or inserting statements) by sequencing statements of the ACL. Named standard ACL:123456R1(config)# ip access-list standard MY_STANDARD_ACLR1(config-std-nacl)# permit 10.1.1.0 0.0.0.255R1(config-std-nacl)# deny 10.2.2.2R1(config-std-nacl)# permit anyR1(config)# interface fastEthernet 0/1R1(config-if)# ip access-group MY_STANDARD_ACL out

Named extended ACL:123456R1(config)# ip access-list extended MY_EXTENDED_ACLR1(config-ext-nacl)# deny icmp 10.1.1.1 0.0.0.0 anyR1(config-ext-nacl)# deny tcphost 10.1.1.0 host 10.0.0.1 eq 80R1(config-ext-nacl)# permit ip any anyR1(config)# interface fastEthernet 0/1R1(config-if)# ip access-group MY_EXTENDED_ACL in

Editing ACL using sequence numbers:1234R1(config)# ip access-list extended MY_EXTENDED_ACLR1(config-ext-nacl)# no 20 ! Deletes the statement of sequence number 20R1(config)# ip access-list standard 99R1(config-std-nacl)# 5 deny 1.1.1.1 ! inserts a statement with sequence 5

Verifying ACLs: Shows all ACLs configured on a router with counters at the end of each statement:123R1# show access-lists! ORR1# show ip access-list

Shows only the specified ACL:1R1# show ip access-list 101

Includes a reference to the ACLs enabled on that interface either in or out:1R1# show ip interface f0/0

DHCP Server Define a DHCP pool and give it a name:1R1(config)# ip dhcp pool MY_POOL

Define network and mask to use in this pool and the default gateway:12R1(dhcp-config)# network 192.168.1.0 255.255.255.0R1(dhcp-config)# default-router 192.168.1.1

Define one or more DNS server (OPTIONAL):1R1(dhcp-config)# dns-server 213.131.65.20 8.8.8.8

Confine the lease time (OPTIONAL):1R1(dhcp-config)lease 2 ! Days

Define one or more scopes of excluded (reserved) addresses (OPTIONAL):12R1(config)# ip dhcp excluded-address 192.168.1.1 192.168.1.100R1(config)# ip dhcp excluded-address 192.168.1.200 192.168.1.254

DHCP Verification and Troubleshooting: Shows the status of the specified pool and the leased addresses from that pool:1R1# show ip dhcp pool POOL_1

Shows all the leased ip addresses from all configured DHCP pools:1R1# show ip dhcp binding

Shows any conflicts that occurred:1R1# show ip dhcp conflict

PPP Configuration:12R1(config)# interface serial 0/0R1(config-if)# encapsulation ppp

PPP Authentication:CHAP: Configure the hostname:1R1(config)# hostname ALPHA

Configure the name of the other end router and the shared password:12! The password used is shared password, that means it must be the same on both routersALPHA(config)# username BETA password XYZ

Enable CHAP authentication on the interface:12ALPHA(config)# interface serial 0/0ALPHA(config-if)# ppp authentication chap

PAP: Configure the hostname:1R1(config)# hostname ALPHA

Configure the name of the other end router and the shared password:1ALPHA(config)# username BETA password XYZ

Enable PAP authentication on the interface and define the username and password to be sent by PAP:123ALPHA(config)# interface serial 0/0ALPHA(config-if)# ppp authentication papALPHA(config-if)# ppp pap sent-username ALPHA password XYZ

PPP Verification and troubleshoot: Shows the encapsulation type and the control protocols of PPP:1R1# show interface s0/0

Useful for viewing the configuration of usernames and passwords used to authenticate PPP:1R1# show running-config

Displays the authentication process of PPP in real time:1R1# debug ppp authentication

Frame Relay:

Multipoint (one subnet) Give the interface an ip address and enable Frame Relay encapsulation:123R1(config)# interface serial 0/0R1(config-if)# ip address 1.1.1.1 255.255.255.0R1(config-if)# encapsulation frame-relay (ietf)

Configure LMI signaling type: (Optional as discussed with ISP):1R1(config-if)# frame-relay lmi-type ansi ! options: ansi, cisco, q933a

Configure Frame Relay mapping:123456789101112R1(config-if)# frame-relay map ip 1.1.1.2 102 broadcast (ietf)R1(config-if)# frame-relay map ip 1.1.1.3 103 broadcastR2(config)# interface serial 0/0R2(config-if)# ip address 1.1.1.2 255.255.255.0R2(config-if)# encapsulation frame-relayR2(config-if)# frame-relay map ip 1.1.1.1 201 broadcastR2(config-if)# frame-relay map ip 1.1.1.3 201 broadcastR3(config)# interface serial 0/0R3(config-if)# ip address 1.1.1.3 255.255.255.0R3(config-if)# encapsulation frame-relayR3(config-if)# frame-relay map ip 1.1.1.1 301 broadcastR3(config-if)# frame-relay map ip 1.1.1.2 301 broadcast

Point-to-point (different subnets; one subnet per subinterface) Enable Frame Relay encapsulation:12R1(config)# interface serial 0/0R1(config-if)# encapsulation frame-relay

Give an ip address to a subinterface and configure its DLCI:12345678910111213141516R1(config)# interface serial 0/0.102 point-to-pointR1(config-subif)# ip address 1.1.1.1 255.255.255.0R1(config-subif)# frame-relay interface-dlci 102R1(config)# interface serial 0/0.103 point-to-pointR1(config-subif)# ip address 2.2.2.1 255.255.255.0R1(config-subif)# frame-relay interface-dlci 103R2(config)# interface serial 0/0R2(config-if)# encapsulation frame-relayR2(config)# interface serial 0/0.201 point-to-pointR2(config-subif)# ip address 1.1.1.2 255.255.255.0R2(config-subif)# frame-relay interface-dlci 201R3(config)# interface serial 0/0R3(config-if)# encapsulation frame-relayR3(config)# interface serial 0/0.301 point-to-pointR3(config-subif)# ip address 2.2.2.2 255.255.255.0R3(config-subif)# frame-relay interface-dlci 301

Frame Relay Verification and troubleshoot: Shows the encapsulation type:1R1# show interfaces serial 0/0

Lists PVC status information:1R1# show frame-relay pvc

Lists DLCI to IP mapping:1R1# show frame-relay map

Lists LMI status information:1R1# show frame-relay lmi

Displays the content of LMI messages:1R1# debug frame-relay lmi

Lists messages about certain Frame Relay events, including Inverse ARP messaeges:1R1# debug frame-relay events

Network Address Translation (NAT):Static NAT: Define the outside and inside interfaces:1234R1(config)# interface serial 0/0R1(config-if)# ip nat outsideR1(config)# interface FastEthernet 1/1R1(config-if)# ip nat inside

Configure static NAT statement:1R1(config)# ip nat inside source static 192.168.1.10 200.1.1.1

Dynamic NAT: Define the outside and inside interfaces Create an ACL that determines the IP addresses thatare allowed to be translated:1R1(config)# access-list 3 permit 192.168.1.0 0.0.0.255

Create a pool of public IP addresses:1R1(config)# ip nat pool PUB 200.1.1.1 200.1.1.6 netmask 255.255.255.248

Configure NAT statement:12345678R1(config)# ip nat inside source list 3 pool PUBNAT Overload (PAT):

The same as dynamic NAT with the use of the overload keyword at the end of NAT statement:

1R1(config)# ip nat inside source list 3 pool PUB overload

NAT verification and troubleshoot: Useful in viewing the configuration of NAT pool and the inside and outside interfaces:1R1# show running-config

Displays access lists, including the one used for NAT:1R1# show access-lists

Shows counters for packets and NAT table entries, as well as basic configuration information:1R1# show ip nat stasitics

Displays the NAT table:1R1# show ip nat translations

Clears all the dynamic entries in the NAT table:1R1# clear ip nat translations *

Issues a log message describing each packet whose ip address is translated with NAT:1R1# debug ip nat